Regulation 15 of S.I. No. 566 (European Union (Large Combustion Plants) Regulations 2012) details the provisions in relation to the malfunction and/or breakdown of abatement equipment and such provisions are also generally defined in the individual combustion plants environmental licence. Among other requirements this regulation specifies that the cumulative duration of unabated operation shall not exceed 120 hours in any 12 month period, and that derogations can only be granted by the EPA in very limited circumstances. In order to assist licensees in the interpretation of licence requirements in relation to the recording and reporting of periods of unabated emissions, the EPA has prepared a guidance document outlining how this requirement of the IED should be interpreted and applied by licensees.